SYDNEY, Australia—A hacker stole non-classified information about Australia’s Joint Strike Fighter program and other military hardware last year after breaching the network of a defense contractor, Australia’s defense industry minister said on Thursday.

About 30 gigabytes of data was stolen in the cyber attack, including details of the Joint Strike Fighter warplane and P-8 Poseidon surveillance plane, according to a presentation on the hack by a government official.

“Fortunately the data that has been taken is commercial data, not military data … it’s not classified information,” Defence Industry Minister Christopher Pyne told Australian Broadcasting Corporation (ABC) Radio.

“I don’t know who did it.”

In a presentation to a conference in Sydney, an official from the Australian Signals Directorate (ASD) intelligence agency said technical information on smart bombs, the Joint Strike Fighter, the Poseidon maritime patrol aircraft and several naval vessels was stolen.

“The compromise was extensive and extreme,” said the official, Mitchell Clarke, in an audio recording made by a ZDNet journalist and broadcast by the ABC.

Clarke said the attacker accessed the small contractor’s systems for five months in 2016, and the “methodical, slow and deliberate,” choice of target suggested a nation-state actor could be behind the raid.